Self-sharpening pencil



NOV. 29, 1966 1 GABLER SELF-SHARPENING PENCIL Filed May 26 19651NVENTOR.

JOSEF GABL 12 BYGLMJAQSQLM United States Patent O 3,288,113SELF-SHARPENIN G PENCIL Josef Gabler, Mainaustrasse 44, Zurich,Switzerland Filed May 26, 1965, Ser. No. 458,900 1 Claim. (Cl. 120-15)This invention relates to a pencil and refers more particularly topencils of the propelling lead type which contain a lead sharpeningdevice.

Prior art pencils of this type consist of a large number of parts andhad to be made on so-called decolletage machines, so that they arerather expensive in manufacture. These pencils were provided with rotaryleads and the sharpening of the leads was time consuming. The assemblyof these pencils was rather complicated due to the extensive use ofscrew threads.

An object of the present invention is the provision of a pencil of thedescribed type which will avoid the drawbacks of prior artconstructions.

Another object is the provision of such a pencil which containssubstantially less parts than prior art pencils and which can be madeinexpensively on pressing machines.

Yet another object is the provision of a pencil of the describedconstruction the lead of which can be slid directly without beingrotated and the sharpening device of which carries out a better andfaster sharpening operation than was possible with prior artconstructions.

A still further object is the provision ofa pencil of this type theparts of which can be assembled quickly and easily by tting them oneinto the other, without extensive use of screw threads.

Other objects of the present invention will become apparent in thecourse of the following speciiication.

In the accomplishment of the objectives of the present invention it wasfound advisable to provide a pencil having a tubular case with a capslidably mounted upon one end of the case. The other end of the case isengaged by a conical tip member which is screwed upon an inner tubularmember capable of a slidable movement limited by the engagement of itsflange with a flange of an inner sleeve iixed within the case. Thesharpening of the lead takes place in the withdrawn position of theinner tubular member by engagement of the lead with blades extending atan acute angle to the axis of the pencil and located upon an innersurface of the conical tip member. The lead located within the pencilcan slide without being rotated by pressing the cap which then moves atube out of engagement with segments normally holding the lead. However,further inner sleeves are also provided permitting a forward movement ofthe lead when the cap is rotated.

The invention will appear more clearly from the following detaileddescription when taken in connection with the accompanying drawingshowing by way of example, a preferred embodiment of the inventive idea.

In the drawing:

FIGURE 1 is a longitudinal section through a pencil constructed inaccordance with the present invention, shown in its working position.

FIGURE 2 is a similar section, but shows the pencil in itslead-sharpening position.

FIGURE 3 is a transverse section along the line III-III of FIGURE 1.

rThe drawing shows a pencil case 1 having at the front end a conical tip2. The tip 2 has a cylindrical portion which is substantially inalignment with the case 1 and which is screwed upon an inner tubularmember 4. A lead 3 extends through the tip 2. At the other end of thecase 1 there is provided a cap 7 having a skirt portion 8 which slidablytits over the rear end of the case 1. The cap 7 which is adapted to movelongitudinally has an 3,238,113 Patented Nov. 29, 1966 inner annularflange enclosing a sleeve 11 which in turn encloses a pin 24. The sleeve11 is provided with a longitudinal slot 12 into which extends aprojection 25 constituting a part of the pin 24. The pin 24 engages thetop of the lead 3.

Substantially in the center of the case 1 is provided a bush 10. Apressure spring 9 extends between the bush 10 and the cap 7 and aroundthe sleeve 11.

A further sleeve 19 surrounds the sleeve 11; its top is spaced a shortdistance from the ange of the cap 7 and it extends through the bush 10ending somewhat below the top edge of the tip 2. The sleeve 19 has aslot receiving the projection 25 and is provided with a helical grooveor threads 18. Another sleeve 22 encloses the sleeve 19. The sleeve 22has a rear end fitting into a recess of the bush 10, and an outwardlycurved ilange 23 which is adapted to engage an inwardly curving end angeof the tube 4. The sleeve 22 ends in a conical portion 17.

A short sleeve 13 is mounted upon the tube or sleeve 11 and is connectedwith a tube 14 embracing the lower end of the lead and terminating inresilient segments 15 which have a tendency to extend outwardly andwhich are provided with curved portions 16.

The inner surfaces of the conical end piece 2 carry a conical sleeve 5provided with cutting blades 6 which are inclined at an acute anglerelatively to the pencil axis.

FIGURE 1 shows the pencil ready for use; the lead extends out of the tip2 and is rmly held in place by segments 15 which are pressed against thelead by the conical member 17 the edge of which engages the curvedportions 16.

To remove the lead the user merely presses down the cap 7 which willslide along with its skirt portion 8 upon the case 1, therebycompressing the spring 9. This sliding movement will be transmitted tothe tube 14; its segments 15 will move beyond the edge of conical member17 and will open, thereby releasing the lead 3. The lead 3 can thenslide outwardly without rotating, due to the provision of the sleeve 13along with the tube 14. However, the user can also shift the lead 3forward gradually in the usual manner by rotating the cap 7, due to theprovision of the described tubular members. To provide a return movementof the lead, the lead must be released by pressure against the cap 7, ashas just been indicated.

To sharpen the lead, the user must pull the conical tip 2 along with thetube 4 until the inwardly curving end of the tube 4 is brought intoengagement with the outwardly curving flange 23 of the sleeve 22. Thenthe tip 2 along with the tube 4 can carry out a limited swingingmovement relatively to the lead 3 engaged by the tube 14, so that thelead 3 can be pressed against the blades 6 of the conical sleeve 5, asillustrated in FIG. 2. Then the end of the lead 3 can be sharpened byturning the tip. After the sharpening operation has been completed thetip 2 is moved back into the position shown in FIG. 1.

It is apparent that the described construction has comparatively fewparts which can be easily stamped out of metal sheets. These parts canbe easily assembled merely by fitting them one over or one into eachother. The possibility of sliding the lead in and out without rotatingit, greatly facilitates handling and preserves the lead from breakage.The inclined arrangement of the cutting blades improves and expeditesthe sharpening of the lead tip.

It is apparent that the example described above has been given solely byway of illustration and not by way of limitation and that it is subjectto many variations and modications within the scope of the presentinvention. All such Variations and modifications are to be includedwithin the scope of the present invention.

What is claimed is:

A self-sharpening pencil, comprising, in combination, a tubular ca se, acap mounted upon one end of said case and slidable thereon, a tubularmember within said case, a conical tip member screwed upon one end ofsaid tubular member and having an end portion substantially aligned withthe other end of said case, lead engaging segments within said case, atube integral with said segments, another tube having an end contactingan end of the rstmentioned tube and another end engaging a cavity insaid cap, a sleeve interconnecting said two tubes adjacent thecontacting edges thereof, another sleeve enclosing the second-mentionedtube and having helical threads thereon, a third sleeve enclosing thesecond-mentioned sleeve and having an outwardly projecting annularilange, a bush fixed within said lcase and engaging an end of thethird-mentioned sleeve, a pin having one end engaging said cap cavityand enclosed by the second-mentioned tube, said pin having a projectionextending through a slot formed in the second-mentioned tube and analigned slot formed in the second-mentioned sleeve, a coiled springengaging said bush and an inner surface of said cap, said tubular memberhaving an inwardly projecting annular ange adapted to engage theoutwardly projecting annular flange of the third-mentioned sleeve whensaid conical tip member and said tubular member are pulled away fromsaid case, and lead sharpening means upon an inner surface of saidconical tip member, said lead sharpening means having blades extendingat an acute angle to the axis of the pencil.

References Cited by the Examiner UNITED STATES PATENTS 1,445,856 2/1923Sonneborn 120-22 X 1,585,843 5/1926 Fitch 120-18 X 1,780,581 ll/1930Dillier 120-15 2,507,089 5/1950 Bridges 1Z0-15 LAWRENCE CHARLES, PrimaryExaminer.

